There is known an image-recording apparatus that includes a liquid chamber configured to store ink therein, and a head configured to eject the ink supplied from the liquid chamber through nozzles (see Japanese Patent Application Publication No. 2015-199261, for example).
Such image-recording apparatus may be provided with a structure for detecting a residual amount of ink stored in the liquid chamber. For example, an image-recording apparatus may include a pivot member pivotably movably supported within the liquid chamber. The pivot member may be configured of material having a specific gravity smaller than that of ink. In case that a liquid surface of the ink stored in the liquid chamber is located higher than a prescribed height, the pivot member is positioned at a prescribed position due to buoyancy of the ink. When the liquid surface of the ink stored in the liquid chamber falls below the prescribed height and a majority of the pivot member is located higher than the liquid surface of the ink, the pivot member is caused to pivot due to gravitational force. This pivotal movement of the pivot member may be configured to be detected by a sensor, so that how much ink is left in the liquid chamber can be detected.